Dogs like to jump. When you watch a group of dogs at play you'll see them jump all over one another, perfectly okay in the doggie world. However, in the human world, it's considered impolite and dogs need to learn how to greet humans in a manner that's acceptable to people. With consistency and lots of positive reinforcement, your dog's jumping problems can be a thing of the past.
Every dog responds to different things. One training method may work wonders with one dog, while it has no effect on another. So below is a list of some techniques to try. Positive reinforcement dog training is key - do not punish! Dogs learn to repeat behavior when they're rewarded for it, so encourage and reward your dog throughout the training process.
If she attempts to jump on you again, then turn your back again. Repeat as necessary. You want to teach her that staying down on the ground means she'll get attention, while jumping up means she'll get ignored.
This may take a while... but practice makes perfect! Be consistent and don't get frustrated. Remember that timing is important - you should greet / praise your pup when all four of her paws are on the ground, not when she's jumping on you.
Teaching this method is actually very similar to the first. Before you begin, your dog should already know how to sit/stay in a normal, calm situation. Now you want her to do it when one of the most exciting things happen - a visitor comes to the door! When your dog jumps on you, ignore her. Wait until her paws are all on the ground, and then say a command, such as "off". Then greet / praise her. Make sure you wait until her paws are on the ground before you give her the command - you want her to associate the command with keeping her paws on the ground, not with jumping up on you!
If you like, you can take the training a bit further. Once her paws are on the ground, ask her to do a sit/stay. After your dog holds a sit/stay, you can have her either offer her paw on cue, or give a single greeting bark. This will give your dog something to think about (and dog lovers find it irresistable).
This will give your dog something to do and use up a bit of energy... plus the dog may be so happy and preoccupied with the toy that he won't be so inclined to jump on you in greeting. Plus it's cute!
Dog jumping problems aren't an uncommon behavior problem ... but fortunately, they're usually not difficult to correct either. The keys are to be consistent with your training; to make sure you get the timing of rewards right; and to make the experience a positive one for both you and your dog.